Characteristics of the physical sleeping environment (temperature, brightness, and noisiness) were associated with later sleep timing and worse sleep quality but not sleep duration among a diverse national sample of young adults.
Key Findings
Results
A 'too hot' sleep environment was associated with greater wake after sleep onset at the between-person level.
Between-person association: b = 9.93 minutes more wake after sleep onset (95% CI [3.64, 16.21], P = .006)
Also associated with lower sleep maintenance efficiency between persons (b = -1.78%, 95% CI [-3.01, -0.54], P = .010)
Sample: n=372 young adults from the Future of Families 'Young Adult Sleep Study', 60% female
Participants wore wrist-actigraphs and self-reported daily for 2 weeks
Results
A 'too hot' sleep environment was associated with lower sleep maintenance efficiency and decreased odds of good sleep quality at the within-person level.
Within-person association with lower sleep maintenance efficiency: b = -0.79% (95% CI [-1.13, -0.45], P < .001)
Within-person association with good sleep quality: 45% decreased odds (OR = 0.55, 95% CI [0.39, 0.79], P = .001)
Within-person findings reflect night-to-night variation within the same individual
Study used multilevel models to separate between- and within-person effects
Results
A 'too noisy inside' sleep environment was associated with lower sleep maintenance efficiency and substantially decreased odds of good sleep quality at the between-person level.
Between-person association with lower sleep maintenance efficiency: b = -2.97% (95% CI [-5.24, -0.70], P = .03)
Associated with 88% decreased odds of good sleep quality (OR = 0.12, 95% CI [0.02, 0.54], P = .006)
Sleep environment factors assessed were temperature, light, and noise disrupting the previous night's sleep
Both actigraphic and self-reported sleep outcomes were examined
Results
A 'too bright' sleep environment was associated with substantially later sleep timing and nearly 90% decreased odds of good sleep quality at the between-person level.
Associated with 90% decreased odds of good sleep quality (OR = 0.10, 95% CI [0.01, 0.61], P = .010)
Associated with later actigraphic sleep onset by 111.05 minutes (95% CI [26.67, 195.42], P = .010)
Associated with later sleep midpoint by 122.95 minutes (95% CI [41.22, 204.69], P = .010)
Associated with later sleep offset by 131.54 minutes (95% CI [39.7, 223.40], P = .010)
Results
Physical sleep environment characteristics were associated with sleep timing and quality outcomes but not sleep duration.
Temperature, brightness, and noisiness were each linked to at least one sleep outcome
No significant associations were found between any of the three environmental factors and sleep duration
Outcomes assessed included actigraphic sleep timing, duration, wake after sleep onset, sleep maintenance efficiency, and self-reported sleep quality
Authors note future research should examine mechanisms by which environmental factors may affect sleep health
Methods
The study used a daily diary and actigraphy design over two weeks among a diverse national sample of young adults.
Sample: n=372 participants from the Future of Families 'Young Adult Sleep Study'
60% female; described as a diverse, national sample
Participants self-reported daily for 2 weeks whether temperature, light, and noise disrupted the previous night's sleep
Wrist-actigraphy was used to obtain objective sleep measures; multilevel models accounted for repeated daily observations nested within persons
What This Means
This research suggests that the physical conditions of a person's bedroom — specifically whether it feels too hot, too bright, or too noisy — are meaningfully linked to how well young adults sleep. The study followed 372 young adults from a diverse national sample for two weeks, having them wear wrist activity monitors and answer daily questions about their sleep environment and sleep quality. The researchers found that on nights when people reported their room was too hot, they were awake more during the night and had less efficient sleep; on nights when rooms were too bright or too noisy, people were much less likely to report good sleep quality, and bright environments were linked to sleeping and waking up significantly later.
An important feature of this study is that it looked at both between-person differences (comparing people who more often reported environmental problems to those who did not) and within-person variation (comparing a person's own better versus worse nights depending on environmental conditions). Both types of analyses revealed meaningful effects, suggesting these environmental factors matter both as stable features of someone's living situation and as night-to-night influences. Notably, while sleep quality and timing were affected, sleep duration was not significantly associated with any of the environmental factors studied.
This research suggests that the physical sleeping environment is an important and potentially modifiable factor for sleep health in young adults. Addressing bedroom temperature, light, and noise — whether through behavioral choices, home modifications, or policy changes affecting housing quality — could be a practical avenue for improving sleep. The authors call for future research to better understand the specific mechanisms by which these environmental factors disturb sleep.
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Dadzie A, Reichenberger D, Shen Y, Master L, Collie A, Mathew G, et al.. (2026). Daily associations between the physical environment and sleep among a diverse, national sample of young adults.. Sleep health. https://doi.org/10.1016/j.sleh.2026.07.010